<!DOCTYPE html>
<html>
<head>
    <script data-main="js/main" type="text/javascript" src="js/require.js"></script>
    <script  type="text/javascript" >
        require(["jquery","a"],function($){
            $(function(){
                console.log("load finished");
            }),function (error) {
                var failedId = error.requireModules && error.requireModules[0];
                if (failedId === 'jquery') {
                    console.log("jquery error")
                }
            }
        })
    </script>
</head>
<body>
<span>body</span>
</body>
</html>